Apparatus for making instantaneous x-ray photographs.



P. DESSAUBR.

iXPPAEATUS FGR MAKING INSTANTANEFW X-RAY PHOTOGRAPHS.

APPLICATION FILED AUG.S,1911.

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original application filed Roi/"ember 8, 1909, Serial No. 526,795.

FRIEDRICH DESSAUER, OF

FRANKFORT-ON-THE-MIN, G

APPARATUS FOR IMAKITG INGTANTANEOUS X-RAY PHDTOGRAPEIS.

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be ii iUl-(IM'H that IRHPIUKBETHQIKS in Apparatus for Ii. iiiii'lllfili), have. invented certain new:

untuneous X-Ruy Photographs .u-es to an apparatus for Specification of Letters Patent.

Dia'l-ied and this application filed August Serial No. 6453.181.

,! of ihe hunting heart SilOW ubsoiuteiv sharp on the ii-lie.

Pictures mum by the ohi methods. and ranging, as sin from one to tweut i' so? 0nd exposure. have almost inrz'uxizilii been i '3' or less frequenti i', :1 ii A the zonilzirv high teng .utuzieous X-ray photographs sion alternating current being iru formed 4 or reference to an iniproveinto high temioii continuous (:iirreiu. There in mean for exposing photographic might be mentioned another expr 'imeniin iFiiitPS med in connection with X-ray phowhich ihe eii eet of an interruption was inregruph the suhjeei-inzitier of thiaappiieacreased to surh un one i-y uii novels-ration 15 tion iiirmii division of a copending apof the rnpi-ziiiy of the interruption that u.

riiczition for puceni, Serial No. 526,795, filed Nov. EH39.

The object in view in this connection is to eou iruet an X121 photograpx'ing apparatus which is capable of effecting an ex reniei ropiwmiposure of the photographic plate 11; well to simplify the structure of h a. mechanism. With this object in i invention will hereinafter be fully and d "ihod, reference being had e gronipmiyin -g drawing in which one zit of my invention is shown. some time viii. hove been made to shot through by means of a pistoi. All these methods J 'hou'evc-r imperfect.

The last uieniioned method is not @uii'nhie because a. mum period of time will ul u pass between i voluntary clos ng the primary ei ii" and its Yohmturv iiiter u r tion. This period is not coutroiiuoie re spouting ti; 1 re: duration of the ma netixihg current, and the ohmic resistance of.

g the Qu-euii': being, ouiy 0.1. an iRFHi'i'iCiCiit eur- Hmri'u the length time required ior tzih- 1'" ii: \Viii he ohtuiumi in putting; 5e i ziy )1Cii1C., :iS to render it posm- 'i eiv tzli'uefi, O1 5111 iluu trul in: untaueous picture.

sow-oiled nmtuuiuueous 0115.5, and eziposiires oi as" uni-1h as eeeiuis hr oeei ueous.

Il a fk en 111 P iililii one .ond, ranging o; quarter to one twenixtier the haul and one can oni when T of ii sruuiu 11" soil on or I I mate. as

iiiielliiiii v or involuntary twenty v zisisiere-i or insoiuizi- 1 Led (uses pictures have resuiiif no ietv re .hie grout-.1 of the current strength wiii .inuces are used.

The presvui invention. by which he pie hue have been made with exposure ru 'ia-uui ififl ji in l/XOOth second, ha

' Hiilfji vXi-iwmeut of the semi" sl ruzer by {he iiii rrup l Liuuuiu: current. Hi-ii u in .oruier used for that gnu-1r i'ormer hein e0i|:-;(riul.ed isiu; izupie inniueiiou eoii. hiii'iiiLl'hlCl'a. i: miiziuuuzm euri'eiii'. hut. in eorurui'ii period of it, with Li. crane-.1 a the rap-h2- .iuu in i iiiLi' up; rug. u".- wmiiuuoi iv I f b morezueiii; or the ohjeei Lo be phi, img mierru; )i'er 1.: Ulil iQ i oi.

' ilil i. such ihe L;- [:Ft oi ziii oriimziry interrupter make exposure imp! tumour: piiol'ogru u'is are 5 he! ihie. :zuai instani'ii ii l iiiu 0m ile rrihrii apparatus. rhiefi because line of theapparatus, with the circuits thereof. In the accompanying drawings, which represent one form of the invention, a is the 5 direct current transformer or induction coil and has one poleof the primary coil connected to' one side of a' current source 5. A -condenser b is connected with one pole in contact with the other terminal of the primary coil of the transformer a, and is furnished of suitable size so that when the primary circuit is broken, the strength of the discharge of current can be raised by the diversion of the current to said condenser and thence back over the line, producing in the secondary coil an induced current of" very high voltage capable of ionizing the X- ray tube. The interval 0f;time between the making and the automatic breaking of the circuit which is completed as hereinafter de scribed is a very short one and depends particularly upon the length of time which is required to withdraw a contact element from a mercury bath. At the instant of withdrawal of said contact from the mercury bath, a n10- mentary resistance is set up in the primary circuit, during which said condenser becomes charged, said charge, as stated, going back over the line when the break in the circuit is made.

In the circuit established between the primary coil of the transformer a, the current source 5, and the condenser b is an automatic switch 0. Said switch is, or may be, of

the lever type or of any other kind and con- .sists of an arm 0 and a leaf which may on ter the fixed contact members, the latter being connected to the condenser terminal. The switch 0 cooperates with a mechanism 40 by means of which it is rendered possible to utilize the single impulse of discharge current. is connected by means of a suitable immersed fixed terminal into the primary circuit between the part 9 of the switch 0 and the condenser b. Immersed in the mercury of the vessel (Z is a movable contact rod f which is adapted to be raised out of the mercury by means of the expansion spring e. The nip.- per end of the rod f is provided with a fixed collar or projection f with which a latch or tappet h is adapted to engage to hold the .rod f in its depressed position. The ta'ppet h is connected to or carried by the switch arm a, so that the movement of the tappet is governed by the action of the latter.

Thus, when the switch arm 0 is thrown oyer" to close the primary circuit the tappet h is withdrawn from the collar or projection f, and the rod f is permitted to snap upwardly under action of the spring 0. Inthe'connection between the tappet It and the switch 0 is inserted a regulating screw 2', by means of whichzthe length of the connection can be adjusted, and consequently the interval of The contents of a mercury vessel d single discharge impulse.

time which elapses between the closing of the switch a and the releasing of the rod f.

The duration of the closing of the circuit must be adustable, 'i. e. it must be brought into accordance with the necessary duration of the magnetizing of the induction coil, no matter whether the means for this adjustability are provided in the apparatus itself or whether they are added to the apparatus separately. 1

In the above described manner the primary circuit is closed by means of the switch c for a period of time which depends first upon the length of the tappet 7t adjustable by means of the screw 2', secondly upon the o length of the rod f which is immersed in the mercury, and thirdly upon the acceleration exercised by a spring e'or byanother start ing device. This period of time being an extremely short one, it is ossible to over- .3 load the machine to a hlgh degreeiiwith safety, and the required impulse of current to cause a single intense excitement ofthe U secondary coil is attained. Thus, it is obf vious that the solution of the problem of'iirl. 9o stantaneous X-ray photography, as 0on templated in this invention, depends on tha possibilityof a momentary high carrying of current, underthe protection of the Cireuit current against excessive overloading gs, and the principal feature of this invention lies in this, that after the switching jo jo the current, a forceful switching p caused after a time which is equal to the 'Iiec j essary duration of the magnetizing Gilt-g 0 rent, and which allows a high overloading without danger. I 1

As already stated, it isipossibleto, load electric machines fora: very ste num terval of time to the extent ,of a "hundred per cent, and by'this apparatus, the .1. overloading is carried out without danger to the machine, by the almostsimultaneous .5 opening of the circuit. 'Tlieldischarge I rent strength can the raised vby'the trails -1 ference of a, current of a' sufici ently. high strength through the transformer and the condenser of suitable size so' that any desired X-ray exposure-can be taken bya v 1155 The characteristics of the present invention are: (l) The voluntary switching on of the apparatus is immediately and automatically followed by an interruption of the primary circuit, by means .of the apparatus as described herein. (2) This interruption pro 9 duced automatically by the closingofJthe. primary circuit permits in the primary of a very high load admissible only for avery I short time. (33 The interruption at break I produces the desired current impulselin the secondary. l) The phenomenon is produced only once by one switching on of the apparatus. (5) As exciting current a direct f current is used. (6) There are two circuits, 13o

all inducing and an induced one. continuously working break is use of.

What I claim is (7) No being made 1. In an apparatus for taking instantane ous Xray photographs, the combination of a directcurrent transformer, a high 'capacity condenser in circuit with the primary of said transformer and a current source, a

jofja direct switch in the circuit, and means mechanically controlled by said switch to break the with the primary of said transformer and a.

current source, a switch in the circuit, and means mechanically controlled by said switch to break the primary circuitat high adjustable interval of load within a short I timeafter the switch is closed. said device consisting of a met-cur cup, a spring pressed contact immersed in said cup and a releasing mechanism operatively disposed between.

said switch and said spring-pressed Contact, whereby the latter is released to spring out of said cup when said switch is closed interrupting the primary circuit.

- In testimony whereof I afiix my signature in presence of two witnesses.

FRIEDRICH DESSAUER. Vitnesses: I

Vomnran Orrrz, Jnax Gnum). 

